For achieving quiet and stable combustion in a gas turbine it is known how to inject operating gas in the form of combustion gas and air premixed by jet carriers into a combustion space, as a result of which very lean combusting with a low accrual of noxious constituents, particularly NOx and CO, can be produced. Compared with spin-stabilized systems, combustion systems of such type based on premixed jet flames offer the advantage that variations in heat release and hence in density or, as the case may be, pressure can be kept low. Unstable and loud combustion can be avoided. Suitably selecting the jet pulse allows small-scale flow structures to be produced that will dissipate acoustically induced heat-release fluctuations and so suppress pressure pulsations that typify spin-stabilized flames.
Combustion stabilizing accompanied by attaining a very high efficiency level and low production of harmful substances can therein be achieved by very heavily diluting the operating gas with waste combustion gases. Instead of there being a visible flame front, non-luminous combustion will take place that is known also as mild, colorless, or volume combustion. A high volume flow of waste gas into the combustion zone can therein be achieved by recirculating waste combustion gases, which preferably takes place inside the combustion space. The recirculated waste combustion gases will dilute the fresh gas brought into the combustion space and also cause the resulting gas mixture to become highly preheated to temperatures above a self-ignition temperature of the operating gas. Instead of a conventional flame front, a voluminous flame zone will be achieved within whose volume virtually even combusting takes place.
Known from DE 10 2005 008 421 A1 is a combustion chamber for a gas turbine, in which chamber waste gas from a combustion process is ducted by means of recirculating into a mixing zone and volume combustion thereby achieved.